1. Field of the Invention
The present invention relates to a vehicular generator having a control device which controls output voltage of the generator according to a command signal sent from a control unit disposed outside the generator.
2. Description of the Related Art
A control device including a voltage regulator for a vehicular generator is usually provided with a power terminal (B-terminal) connected to a high-side terminal of a rectifier of a generator, a ground terminal (E-terminal) connected to a low-side terminal, a phase voltage terminal (P-terminal) connected to a phase winding and an ignition terminal (IG-terminal) connected to the key switch of a vehicle. Such a control device may be provided with a terminal (FR-terminal) for sending generator condition to a control unit outside the generator and a terminal (C-terminal) for receiving a generator command signal from the outside control unit through a signal wire.
For example, U.S. Pat. No. 4,672,297 (or JPU 60-181200, the corresponding publication) proposes a control device for a vehicular generator in which the device sends a field-current signal to an outside control unit. A control device disclosed in JPA 60-109731 applies a battery voltage to a terminal of a charge lamp (L terminal) through the ignition switch of a vehicle and the lamp to detect turn-on of the ignition switch.
However, such a device is provided with various terminals, which necessitates considerable wiring works and wiring space.
Although the series connection of the lamp and the ignition switch disclosed in JPA 60-109731 may reduce cost, a failure of the lamp may cause trouble with the regulator operation.